Analysis On The Characteristics Of Balck And Odorous Pollution And Study On The System Control Scheme In Shitou River Basin

At present,the state vigorously promotes urban ecological construction,and the requirements for urban aquatic ecological environment are further increased.The black and odor pollution problem in the stone river basin in the east of Hegang City is serious,and the backward municipal construction can no longer build a good water ecological environment.Therefore,it is very urgent to rectify the black and smelly river and restore the ecological background.The black and odorous water treatment project needs to adapt to local conditions,control the whole as a whole,and coordinate and coordinate various technical links.Otherwise,it is not only difficult to control black and odor pollution,but also cause the loss of capital and resources.This subject takes the Stone River Basin in the east of Hegang City as the main body of study,and based on the data investigation and test data,the pollution characteristics of the water bodies and sediments in the river basin are analyzed.The relative pollution of the water bodies by each pollution source is quantitatively analyzed using the source list method Contribute to the evaluation and source analysis of heavy metal pollution in sediments.On this basis,based on the changes in water quality during the implementation of the first phase of the watershed water treatment project,an analysis of the effectiveness of the treatment was carried out.Based on the chemical leaching method,the process parameters and mechanism of the safe disposal of the sediment were explored.With a view to providing suggestions for the overall management of the basin.Concluded as follow:According to monitoring and investigation,there are two "heavy black and odorous pollution" channels in the river basin: Shitou River and Longxugou,and the rest are "lightly black and odorous pollution" channels.Taking the black and odorous rivers in the Shito River Basin as the research object,the source list method was used to analyze the black and odorous pollution sources.The analysis shows that in terms of COD,the main pollution sources in the Shitou River Basin are industrial point sources?52.69%?and combined overflow point sources?23.68%?.At the same time,by analyzing the content and morphology of heavy metals in the sediment,the results show that the excess heavy metals in the sediment are Cr and Ni;the Nemero pollution index PN=1.44,which is mild heavy metal pollution;Ni,Zn,Pb,Cu is mainly in a state of easy migration,and there is a risk of heavy metal pollution and diffusion;it is speculated that heavy metals mainly come from three functional areas: residential areas,industrial areas,and traffic areas near rivers.In order to realize the safe treatment and disposal of the bottom mud of the stone river,chemical leaching test research was carried out.The results show that after the sediment is washed with FeCl₃,it can meet the requirements of landscaping.The optimum process parameters at room temperature are: FeCl₃ solution concentration 0.7mol/L,solid-liquid ratio 1:15,time 10 h.After sufficient shaking and washing,the residual Cr and Ni contents in the bottom mud are 593.20mg/kg and 69.90,respectively.mg/kg,lower than the requirements of Cr<600mg/kg and Ni<100mg/kg in the standard of "Urban Sewage Treatment Plant Sludge Disposal Sludge for Landscaping and Landscaping".Further analysis shows that FeCl₃ mainly removes Cr in the carbonate-bound state and Ni in the organic-bound state and the carbonate-bound state.It can provide a theoretical basis for the safe treatment and disposal of the bottom sediment of the stone river.Through the implementation of related projects such as interception,dredging,water replenishment and greening in the first phase of the project,the overall water quality of the river basin has been significantly improved.Monitoring the water quality during treatment showed that the ammonia nitrogen concentration in the Shitou River Basin decreased from 9-21 mg/L to 3-13 mg/L,a reduction of 14.6%-66.4%.The dissolved oxygen concentration increased from 0.2?0.8mg/L to 1.1?4.3mg/L.Transparency is maintained at 15cm?29cm.The ORP value can be maintained above 0.But there is still a risk of recurrence of black smell.Subsequent governance should focus on ecological restoration and build a good aquatic ecological environment.